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Question
See the given figure. DE || BC. Find AD.
Solution
It is given that DE || BC
By using basic proportionality theorem, we obtain
`("AD")/("DB")=("AE")/("EC")`
`("AD")/7.2=1.8/5.4`
AD × 5.4 = 1.8 × 7.2
AD = `(1.8 xx 7.2)/5.4`
= `18/10xx 72/10 xx10/54`
= `24/10`
= 2.4
∴ AD = 2.4 cm
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